Self-locking mechanism of manually tightened drill chuck

ABSTRACT

The present invention publicly discloses a self-locking mechanism of a manually tightened drill chuck, including a ratchet wheel, a clamp bearing, at least one resilient pawl, and a clip ring, wherein said ratchet wheel is fixed in connection with the main unit of said manually tightened drill chuck, and on its back there are provided ratchet teeth facing the end surface of said main unit; said clamp bearing is fixed in connection with the outside surface of a screw ring on said manually tightened drill chuck, and the end surface of this clamp bearing is provided with at least one ratchet wheel slot; said resilient pawl is fixed on said ratchet wheel slot, and it includes a protuberance and a tooth piece; and said clip ring includes at least two arc segments that can mutually antagonistically snap onto the front end position of said main unit, the outer perimeter surface of this clip ring is fixed in connection with a front cap of said manually tightened drill chuck, said clip ring is connected with said clamp bearing and drives said clamp bearing to rotate, and the end surface of said clip ring is provided with deep and shallow recesses for receiving the protuberance on said resilient pawl.

FIELD OF TECHNOLOGY

The present invention relates to an area of mechanical technology, andmore concretely, it relates to a self-locking mechanism of a manuallytightened drill chuck.

BACKGROUND TECHNOLOGY

A manually tightened drill chuck is a commonly used tool in daily life,and mainly it is used for boring and drilling holes when installing orfixing articles. If a manually tightened drill chuck is not providedwith a self-locking mechanism, as shown in FIG. 1, the drill's forcefulvibrations in the course of use can easily cause the drill bit on thefront end to loosen, affecting the bore quality, or, in severe cases, tobreak, which is dangerous.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a self-lockingmechanism of a manually tightened drill chuck that will prevent thedrill bit of the manually tightened drill chuck from loosening andbreaking in the course of use.

The self-locking mechanism of a manually tightened drill chuck of thepresent invention includes a ratchet wheel, a clamp bearing, at leastone resilient pawl, and a clip ring, wherein:

said ratchet wheel is fixed in connection with a main unit of saidmanually tightened drill chuck, and on its back there are providedratchet teeth facing the end surface of said main unit;

said clamp bearing is fixed in connection with the outside surface of ascrew ring on said manually tightened drill chuck, and the end surfaceof this clamp bearing is provided with at least one ratchet wheel slot;

said resilient pawl is fixed on said ratchet wheel slot, and it includesa protuberance and a tooth piece; and

said clip ring includes at least two arc segments that can mutuallyantagonistically snap onto the front end position of said main unit, theouter perimeter surface of this clip ring is fixed in connection with afront cap of said manually tightened drill chuck, said clip ring isconnected with said clamp bearing and drives said clamp bearing torotate, and the end surface of said clip ring is provided with deep andshallow recesses for receiving the protuberance on said resilient pawl.

The end surface of said clip ring is provided with at least oneprotuberance, and the end surface of said clamp bearing is provided witha recess corresponding with this protuberance and having a width largerthan the protuberance.

The end surface of said clip ring is provided with at least one recess,and the end surface of said clamp bearing is provided with aprotuberance corresponding with this recess and having a width smallerthan the recess.

Said ratchet wheel is integrally formed with said main unit, and saidratchet teeth are directly formed on the end surface of said main unit.

The outer perimeter surface of said clip ring is tight-fitted with saidfront cap by means of a raised rib and a recess.

The inner perimeter surface of said clamp bearing is tight-fitted withthe outer perimeter surface of said screw ring by means of a raised riband a recess.

Said ratchet teeth are replaced by recesses, pits or holes.

A manually tightened drill chuck, including a self-locking mechanismdescribed above.

The manually tightened drill chuck of the present invention can realizethe purpose of self-locking after installing the self-locking mechanism,and it has the advantages of convenience of installation, simplicity ofoperation, and self-locking effectiveness.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic in sectional view of a manually tightened drillchuck when the self-locking mechanism of the present invention has notyet been installed.

FIG. 2 is a schematic in sectional view of a manually tightened drillchuck after the self-locking mechanism of the present invention has beeninstalled.

FIG. 3 is a schematic in sectional view when the self-locking mechanismof the present invention is installed and is in the locked state.

FIG. 4 is a three-dimensional exploded view of a manually tighteneddrill chuck with the self-locking mechanism of the present inventioninstalled.

FIG. 5 is a three-dimensional exploded view of the self-lockingmechanism of the present invention.

SPECIFIC EMBODIMENTS

Specific embodiments of the present invention are explained in furtherdetail below along with the attached drawings.

Embodiment 1

As shown in FIG. 2 through FIG. 5, the self-locking mechanism of amanually tightened drill chuck of the present invention includes aratchet wheel 2, a clamp bearing 4, two resilient pawls 5, and a clipring 7, wherein:

the ratchet wheel 2 is fixed on the end part of the inner cavity of themanually tightened drill chuck main unit 1 by means of a connectingmember, such as a screw, screw bolt or nut screw (not illustrated in thedrawings) or a tight fitting, and furthermore on its back there areprovided ratchet teeth 20 facing the end surface of the manuallytightened drill chuck main unit 1.

The clamp bearing 4 is directly fixed on the outer perimeter surface ofa screw ring 3 of the manually tightened drill chuck, and one canconnect the clamp bearing 4 and the outer perimeter surface of the screwring 3 by using a tight-fitting or connecting member (one can also placeraised ribs, protuberances, recesses, pits, holes, hooking mechanisms,etc., that mutually snap together between the clamp bearing 4 and theperimeter surface of the screw ring 3). That is, the clamp bearing 4 andthe screw ring 3 rotate together. The outside edge of the end surface ofthis clamp bearing 4 is provided with two recesses 40 and two pawl slots41 (the number of recesses and pawl slots can be changed according todifferent requirements).

The two resilient pawls 5 respectively are installed on the two pawlslots 41 of the clamp bearing 4, and each resilient pawl 5 includes aprotuberance 50 and an uplifted tooth piece 52. The shapes of theseresilient pawls 5 can be all kinds of shapes other than thoseillustrated in the drawings, and one can use all kinds of connectingmethods such as welding, riveting, and adhesion to fix these to theclamp bearing 4.

The clip ring 7 includes two semicircular arc segments that can mutuallyantagonistically snap onto the front end position of the manuallytightened drill chuck (simply called two-piece clip ring), and afterbeing snapped onto the front end position of the drill chuck, theycannot move in the axial line direction, but they can rotate freely inthe radial direction. The outer perimeter surface of this clip ring 7 istight-fitted with a front cap 6 of the manually tightened drill chuck,and on its end surface there are provided protuberances 70 that cancorrespondingly fit with the recesses 40 of the clamp bearing 4. At thesame time, there are provided deep and narrow alternating recesses 71,72 that can receive the resilient pawls 5, of which the width of theprotuberances 70 is smaller than the width of the recesses 40, so as toenable the clip ring 7 to rotate a fixed angle, given that the clampbearing 4 does not rotate.

The principle of operation of the self-locking mechanism in the presentinvention is:

As shown in FIG. 2 and FIG. 3, during installation the deep recesses 71on the end surface of the two-piece clip ring 7 are aligned with theprotuberances 50 of the resilient pawls 5, and the protuberances 70 onthe end surface of the clip ring 7 are aligned with the recesses 40 onthe end surface of the clamp bearing 4. When work with the manuallytightened drill chuck requires locking of the drill bit, one turns thefront cap 6 to drive the two-piece clip ring 7 to rotate. At this time,since the protuberances 50 of the resilient pawls 5 are in the deeprecesses 71 on the end surface of the two-piece clip ring 7, there is afixed resilient resistance acting against the two-piece clip ring 7 asit rotates past a fixed angle while the protuberances 70 on the clipring 7 rotate the clamp bearing 4 (the resilient pawls 5 can not yet bepressed down by the two-piece clip ring 7). But when the clip ring 7drives the clamp bearing 4 to rotate, it furthermore drives the screwring 3 to rotate until it takes part in tightening the drill bit. Onecontinues to turn the front cap 6, and at this time, the clamp bearing 4is subject to resistance and cannot rotate, and the front cap 6continues to drive the two-piece clip ring 7, forcing it to rotatethrough a fixed angle, while correspondingly compelling theprotuberances 50 of the resilient pawls 5 mounted on the clamp bearing 4to move along the deep recesses 71 on the end surface of the two-piececlip ring 7 to the shallow recesses 72, causing the protuberances 50 ofthe resilient pawls 5 to be moved in position into the shallow recesses72 of the clip ring 7, causing the resilient pawls 5 to move up, asshown in FIG. 2 and FIG. 3. Thus, it causes the tooth pieces 52 of theresilient pawls 5 to click into the ratchet teeth 20 of the ratchet 2,as shown in FIG. 3. Since the ratchet teeth 20 on the ratchet wheel 2are placed facing one direction, the screw ring 3 can only rotate towardone direction, and at this time, one continues to turn the front cap 6and clip ring 7 until the protuberances 50 of the resilient pawls 5 moveto the ends of the shallow recesses 72 of the clip ring 7 and realizethe purpose of self-locking. When it is necessary to loosen the drillbit, one turns round the front cap 6 and drives the clip ring 7 causingthe two-piece clip ring 7 first to turn past the angle it was forced torotate past when tightening, and at this time, the resilient pawls 5return to the position in the deep recesses 71 of the clip ring 7, andthe tooth pieces 52 of the resilient pawls 5 separate from the ratchetteeth 20. Continuing to turn the front cap 6 will drive the clampbearing 4 to rotate with the screw ring 3 until the drill bit isloosened.

Embodiment 2

The self-locking mechanism of the present embodiment is basically thesame as in embodiment 1 described above, and the only difference is thatthe self-locking mechanism of the present embodiment is provided with aratchet wheel 2, but it has ratchet teeth 20 directly placed on the endsurface of the inner cavity of the manually tightened drill chuck mainunit 1. Also these ratchet teeth 20 can be replaced by protuberances,depressions, holes, pits, etc., realizing the purpose of self-locking injust the same way.

In addition, the clip ring 7 in the self-locking mechanism of thepresent invention can be composed of three, four, or more arc segmentsthat can mutually antagonistically snap together as one body. Also theouter perimeter surface of this clip ring 7 is provided with a structurethat can be mutually fitted and fixed with the front cap, such asprotuberances, raised ribs, recesses, holes, or pits.

In addition, one point is emphasized here, that the recesses 40 andprotuberances 70 on the clamp bearing 4 and the clip ring 7 inEmbodiment 1 described above can be swapped, that is, the protuberancesare placed on the clamp bearing 4 and the recesses are placed on theclip ring 7, and all that is necessary is to make the clip ring 7 andthe clamp bearing 4 again rotate together after having a relative angleof rotation.

To sum up the above, the self-locking mechanism of the present inventioncan achieve the purpose of self-locking after being installed on themanually tightened drill chuck, and it is easy to use and safe andreliable.

1. A self-locking mechanism of a manually tightened drill chuck,comprising a ratchet wheel, a clamp bearing, at least one resilientpawl, and a clip ring wherein: said ratchet wheel is fixed in connectionwith a main unit of said manually tightened drill chuck, and on its backthere are provided ratchet teeth facing the end surface of said mainunit; said clamp bearing is fixed in connection with the outside surfaceof a screw ring on said manually tightened drill chuck, and the endsurface of this clamp bearing is provided with at least one ratchetwheel slot; said resilient pawl is fixed on said ratchet wheel slot, andit includes a protuberance and a tooth piece; and said clip ringincludes at least two arc segments that can mutually antagonisticallysnap onto the front end position of said main unit, the outer perimetersurface of this clip ring is fixed in connection with a front cap ofsaid manually tightened drill chuck, said clip ring is connected withsaid clamp bearing and drives said clamp bearing to rotate, and the endsurface of said clip ring is provided with deep and shallow recesses forreceiving the protuberance on said resilient pawl.
 2. A self-lockingmechanism of a manually tightened drill chuck as described in claim 1,wherein the end surface of said clip ring is provided with at least oneprotuberance, and the end surface of said clamp bearing is provided witha recess corresponding with this protuberance and having a width largerthan the protuberance.
 3. A self-locking mechanism of a manuallytightened drill chuck as described in claim 1, wherein the end surfaceof said clip ring is provided with at least one recess, and the endsurface of said clamp bearing is provided with a protuberancecorresponding with this recess and having a width smaller than therecess [sic].
 4. A self-locking mechanism of a manually tightened drillchuck as described in 1, wherein said ratchet wheel is integrally formedwith said main unit, and said ratchet teeth are directly formed on theend surface of said main unit.
 5. A self-locking mechanism of a manuallytightened drill chuck as described in claim 1, wherein the outerperimeter surface of said clip ring is tight-fitted with said front capby means of a raised rib and a recess.
 6. A self-locking mechanism of amanually tightened drill chuck as described in claim 1, wherein theinner perimeter surface of said clamp bearing is tight-fitted with theouter perimeter surface of said screw ring by means of a raised rib anda recess.
 7. A self-locking mechanism of a manually tightened drillchuck as described in claim 1, wherein said ratchet teeth aresubstituted by recesses, pits or holes.
 8. A self-locking mechanism of amanually tightened drill chuck as described in claim 1, said resilientpawl is fixed in connection with said clamp bearing by welding, rivetingor adhesion method.
 9. A manually tightened drill chuck, comprising: achuck body; means for securing a drill bit to the chuck body, thesecuring means being configurable in at least a first and second states,wherein the drill bit is secured to the chuck body when the securingmeans is configured in the first state, and is released from the chuckbody when the securing means in configured in the second state; andmeans for locking the securing means in the first state.